Technical Field

The present invention relates to a space element of the type mentioned in the preamble of claim 1. A method of manufacturing the space element is also disclosed, as is the use thereof for securing sufficient ventilation of insulated constructive structures.

A space element of this type is a universally applicable constructive element as it can be used wherever reinforcement and/or support is required; e.g. in connection with furniture structures of different types, but especially within building construction to provide ventilation cavities or passages under roofs, floors and in similar places, especially in insulated cavity wall structures. The space element according to the invention has a so-called honeycomb structure.

Prior art Considering the high degree of focus at present attached to indoor climate problems it is important that adequate ventilation should be secured in dwellings. To this end, various building regulations dictate certain minimum values which are, however, not observed very often as it is difficult with prior art means. This is because the prior art space elements and honeycomb structures of this type are only found in given, i.e. fixed dimensions and thicknesses. For work where it is required for reasons of mounting and space that a space strip can be made to expand after being fitted in a permanent position, e.g. between two building elements, there are, as far as it is known, no solutions that can be used in practice today.

Description of the invention The main purpose of the present invention is to provide a space strip which can be distributed and mounted in the compact (collapsed) form, and which in an easy and uncomplicated way can be made to expand, i.e. become thicker, after it has been fitted in a permanent position. Besides, it should preferably be possible to anchor or lock the space strip in the expanded form without any major preparations.

The main purpose is achieved according to the invention by a space element as described in claim 1. The two profiles can be displaced parallel toward each other or away from each other by subjecting the free ends of the profiles to pull and/or pressure, whereby the angle α is changed. In this way the ribs produce the expansive effect aimed at when the two longitudinal profiles are displaced relative to each other. The displacement can, of course, be made without the use of tools, that is by affecting the free ends of the profiles by pulling and pressing respectively. In other words: The degree of expansion of the space strip can be changed by displacing the two profiles relative to each other. In the expanded form the space strip has a

honeycomb-like structure which imparts high strength and rigidity to the space strip compared to weight and quantity of material. Completely collapsed, i.e. with the ribs folded closely against the profiles, the space element according to the invention has a minimum thickness. Therefore, it can be mounted even in places with difficult access, e.g. between the outer wall and the insulation in a finished cavity wall structure. After insertion in a permanent position in the cavity wall which can, for example, be done by displacement in between the building elements from above, the space element is expanded by exerting a pull/pressure at the profiles until the expansion required has been achieved. A suitable ventilation cavity now exists between the outer wall and the insulation, thus permitting air circulation and an advantageous venting and drying of the insulated cavity wall.

The statement that the profiles are parallel and straight, is correct in that they are in all essentials parallel and straight. The space element according to claim 1 comprises two such profiles, but may well consist of more than two, e.g. three. The profiles are mainly rigid, as opposed to the ribs which are flexible.

Several space elements of this type may also be combined, e.g. next to each other, resulting in a so-called multiple space element with more than two profiles and a number of rows of ribs which equals the number of profiles minus one. They also form a honeycomb-like structure with the well-known features of this structure. The degree of expansion of such a multiple element is increased relative to the simple element with just two profiles.

The displacement area of a rib can be a completely plane surface, a slightly curved or corrugated surface or a surface with relief, holes or stamps. In these circumstances it will be possible to define a plane in a primary dimension for the displacement area which with one profile defines an angle α. The displacement area is preferably a plane surface.

The attachment area for a rib may have any shape, and the attachment as such can be carried out in any way which is obvious to the skilled man, e.g. by gluing, soldering or welding, or by nailing, screwing, riveting or stapling. All depending on the materials chosen and the strength required.

The said variability of the angle α through parallel displacement of the profiles away from or toward each other can be obtained e.g. by the use of ribs which are themselves flexible, either by virtue of a material flexible in itself and/or by virtue of a special design with e.g. areas of reduced thickness.

Preferably, the ribs comprise pre-fabricated deformation or bending zones at the very connecting points with the profiles or in the close proximity of said points. The bending zones may have been produced e.g. by pre-bending of the rib material or by stamping, and thus having the effect that the angle of the ribs can be changed relative to the profiles by parallel displacement of the two profiles relative to each other as the ribs are deformed when bent in the bending zones. During this process those parts of the ribs which are between the bending zones remain unchanged in all essentials, i.e. straight or only slightly curved.

For reasons of economy identical rib sections are mainly used. However, the rib sections need not be identical, they just have to "work together" in the right way during parallel displacement of the profiles. When thus each rib section is connected to one profile in one attachment area (one end) and to the other profile in the other attachment area (the other end), all rib sections of this preferred embodiment will run parallel and at the same variable angle α relative to the profiles.

Preferably, the rib sections are placed at the same mutual distance. A reliable, uniform displacement movement is thereby obtained. But a constant distance is not required to obtain the expansion effect.

A space strip comprising a space element according to the invention can advantageously be arranged for locking in an expanded position, the two profiles being fixable relative to each other at least at one end of the space strip. Such fixing can be performed in any way, most expediently by stapling or gluing.

In a preferred embodiment the ribs (or at least sections of these) are made of one continuous length of material which is bent and folded to a shape with displacement areas in the form of rib parts, and attachment areas in the form of feet parts in continuation of each other and creating directly the rib shape required after being suitably glued in between the two profiles. The result is a very simple manufacture of space strips.

In what follows, the invention will be described further with reference to the drawing which shows some preferred embodiments of the space element according to the invention.

Description of the drawing Fig. 1 shows a side view of a space strip with a space element according to the invention, shown in the collapsed condition; Fig. 2 a cross section of the same along line A-A in Fig. 1 ; Fig. 3 the same space strip as in Fig. 1 , but now shown in the expanded condition;

Fig. 3a an enlarged section of the space strip in Fig. 3;

Fig. 4 a cross section along line B-B in Fig. 3;

Fig. 5 a front view of the space strip in Fig. 3;

Fig. 6 a horizontal cross section of an insulated cavity wall structure with inserted (expanded) ventilatory space strips;

Fig. 7 a front view of the same cavity wall structure;

Fig. 8 a section showing the interlocking of the two profiles by stapling after expansion of the space strip;

Fig. 9 a front view of the space strip with interlocked profiles in Fig. 8; Fig. 10 a preferred embodiment with a continuous rib section folded from one continuous length of material;

Fig. 11 the rib section in Fig. 10 glued in between the two strip profiles and with the space strip in the expanded condition; and

Fig. 12 the same as in Fig. 11, but in the partly collapsed condition.

Examples of embodiment

Figs. 1-5 of the drawing show an embodiment of a space element according to the invention.

The space element shown consists of two straight profiles 1 and 2 placed parallel to each other, as well as a number of ribs 3 glued in between these profiles. Profiles 1 and 2 can e.g. be made of synthetic material like plastics, by extrusion or die casting, of metal or wood; the ribs 3 of stiff paper or cardboard, synthetic material like plastic, if desired in the form of laminated plastic. The choice of material must, of course, be adapted to the application planned.

Thermoplastic can be used for profiles and ribs; thermosetting plastic, possibly reinforced, can also be used for the profiles. Among usable types of plastic can be mentioned polyethylene, polypropylene, polyvinyl chloride, polystyrene, acrylic plastic, ABS-plastic, polyamide and polycarbonate (all thermoplastics) as well as phenolformaldehyde, carbamid-formaldehyde, melamine-formaldehyde (thermosetting plastics). The list is not exhaustive.

In the embodiment shown, the ribs 3 are all identical and placed at the same (variable) angle α relative to the profiles. Each of the ribs shown has a displacement area 4 in the form of a substantially straight centre section having at each end a flap which constitutes the attachment areas 5 and for the rib's attachment by gluing to the respective profile 1 or 2. Displacement of the two profiles relative to each other changes the rib angle α and thus the distance between the profiles. This property is used to render the space strip expansive so that it can be mounted in the compact form (see Fig. 1), and only after being placed in the permanent position is the space strip expanded to the thickness required in the place concemed. If necessary, the expansion can be carried out without the use of tools. In the embodiment shown, the variation

of angle α is planned to lie between 0 and 90°, but the said angle can also be larger than 90°, perhaps close to 180° if desirable.

Figs. 6, 7 and 8 show an example of a space element according to the invention used as a ventilatory element in a cavity wall 6 consisting of outer wall 7, insulating bats 8 and rear wall 9. After building of the wall to full height the space strips are pushed vertically down between the outer wall 7 and the insulation 8. This is possible because of the small thickness of the space strip before the expansion. Only when the space strip is in position in the wall, is the expansion carried out by exerting a manual pressure/pull at the profiles 1 , 2 at the end of the profiles which project above the cavity wall. After the expansion the profiles are interlocked, e.g. by stapling the two profiles to each other as shown in Figs. 8 and 9, whereby the expanded position is frozen. A number of vertical spacers have now been established between the outer wall and the insulation which in connection with the normal ventilation openings 10 of the wall secure a desired air circulation and drying inside the insulated cavity wall itself.

Figs. 10, 11 and 12 show continuous sections of ribs made by folding one continuous length of material 11 and glued in between two strip profiles 12 and 13. The embodiment distinguishes itself by being very simple from a construction point of view and is at the same time suitable for being prepared by an industrialised process whereby the manufacturing costs can be kept at a reasonably low level.

A suitable material for the ribs in the space element according to the invention is stiff paper, cardboard, plastic foil, metal foil or a laminate of two or more such materials. Preferably, each rib has a flap at each end which is glued orthermo welded to the profile concemed.

A suitable material for the profiles is bending resistant materials, e.g. extruded or die cast plastic, metal or wood of a suitable flat-profile design, the profiles preferably bearing against each other with their flat sides and with the ribs fixed inbetween.

Mainly, the space element according to the invention is supplied in long "endless" lengths, i.e. intended for being shortened to the length required at the very place of use, i.e. for mounting. Otherwise, dimensions and choice of material are, of course, adapted to the field of application which within the field of construction, besides the said cavity walls, can be: Insulation slots under floors, air-sound insulation under wooden floors at floor decks, joists under laminated floors, stretching of underroof (the element can be placed both on top of and under the underroof), ventilation slots under flat roof structures, ceilings, etc. As regards furniture-making, the following fields of application can be mentioned where it is especially used for collapsible furniture: ladders, garden furniture, especially tables, shelves, deck chairs and lounge beds.

The preferred embodiment

Both profiles and ribs are made of plastic for use in connection with insulation of cavity walls. The ribs are made sectionally continuous with a pre-deformed structure in meander configuration as shown in Fig. 10-12 on the drawing. The width of the rib band is 16 mm in this case, which also corresponds to the distance between the displacement surfaces of the individual ribs. The width of the profiles is 2 cm (Fig. 5), and the thickness of the entire space element in the collapsed form is 2-2.5 mm. Completely expanded (Fig. 11) the thickness is 18 mm. Supplied in endless lengths.

A somewhat larger space element with a thickness of 10-40 cm, typically 20 cm, is used horizontally in the loft over cavity walls of this design.